title: Phorbol ester-induced podosomes in normal human bronchial epithelial cells.
abstract: Spreading and migration of the basal cells neighboring a wound is essential for airway epithelial repair. To gain insight into the molecular mechanisms that govern these cellular processes, we asked whether normal human airway epithelial cells can form podosomes, a cellular structure discovered from cancer and mesenchymal cells that controls migration and invasion. Herein, we report that phorbol-12, 13-dibutyrate (PDBu), a protein kinase C activator, induced reorganization of cytoskeletal structure in primary normal human bronchial epithelial cells, and in normal human airway epithelial BEAS2B cells. Z-stack scanning confocal microscopy showed that PDBu-induced podosome-like structures contain actin-rich columns that arise from the ventral surface of the cell, and also revealed the presence of circular ruffles/waves at the dorsal cell surface. The molecular components of these cytoskeletal structures were determined with immunofluorescent staining. Using in situ zymography, we demonstrated that PDBu-induced podosomes were capable of degrading fibronectin-gelatin-sucrose matrix. PDBu also increased epithelial cell invasion across Transwell chamber. Podosomes and circular dorsal ruffles may be important for epithelial cell migration and invasion, thus contributing to respiratory epithelial repair and regeneration.
authors.affiliation: Division of Cell and Molecular Biology, University Health Network Toronto General Research Institute, Toronto, Ontario, Canada.
authors.forename: Helan
authors.initials: H
authors.lastname: Xiao
authors.forename: Rob
authors.initials: R
authors.lastname: Eves
authors.forename: Christina
authors.initials: C
authors.lastname: Yeh
authors.forename: Wayne
authors.initials: W
authors.lastname: Kan
authors.forename: Feng
authors.initials: F
authors.lastname: Xu
authors.forename: Alan S
authors.initials: AS
authors.lastname: Mak
authors.forename: Mingyao
authors.initials: M
authors.lastname: Liu
mesh_terms: D001980:Bronchi / Q000166:cytology*; D002460:Cell Line; D021961:Cell Membrane Structures / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism*; D002465:Cell Movement / Q000187:drug effects; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology* / Q000187:drug effects* / Q000201:enzymology; D005109:Extracellular Matrix / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D020782:Matrix Metalloproteinases / Q000378:metabolism; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology*; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011554:Pseudopodia / Q000187:drug effects / Q000378:metabolism; D016596:Vinculin / Q000378:metabolism
chemical_list: D016596:Vinculin; D015240:Phorbol 12,13-Dibutyrate; D011505:Protein-Tyrosine Kinases; D020782:Matrix Metalloproteinases